Safety-latch for elevator-doors.



T A. MELVILLE.

SAFETY LATCH FOR ELEVATOR DOORS.

APPLICATION FILED MAR-21.19H.

1,256,348. Patented Feb. 12, 1918.

A fro/mus Fig.1.

T. A. MELVILLE.

sum LATCH FOR ELEVATOR nouns.

APPLICATION FILED MAR. 27. I917.

LQ56,348. Patented Feb. 12,1918.

2 SHEETS-SHEET 2.

a N as MIL/EN TOR 7720mm AMeZvJJ/e ATTORNEYS WKTED @TATE% PATENT @FFKQE.

THOMAS ACKERSON MELVILLE, OF FARGO, NORTH DAKOTA.

SAFETY-LATCH FOR ELEVATOR-DOORS.

Application filed March 27, 1917.

To all whom it may concern:

Be it known that I, THOMAS A. MELVILLE, a citizen of the United States, and a resident of Fargo, in the county of Cass and State of North Dakota, have invented a new and Improved Safety-Latch for Elevator- Doors, of which the following is a full, clear, and exact description.

My invention has for its object to provide a safety latch for elevator doors which cannot be operated except when the elevator control lever is in inoperative position, the operation of the safety latch scrvin to lock the elevator control lever in the said inoperative position.

In carrying out my invention no unusual amount of clearance is required between the elevator car and the elevator shaft wall. When the elevator control lever is in inoperative position, a lever may be operated to lock the elevator control lever and to throw a plunger on which a bracket is mounted, a member on the bracket engaging the latch on the door to operate the latter. A member on the latch serves to move the bracket on its pivot when the door is opened to a position where the bracket is locked against a casing member which serves to lock the mechanism in the elevator car until the door is closed.

Additional objects of the invention will appear in the following specification in which the preferred form of the invention is disclosed.

In the drawings similar reference characters denote similar parts in all the views,

in which Figure 1 is a fragmentary view of an elevator car and an elevator shaft door provided with my invention;

Fig. 2 is a side elevation of Fig. 1;

Fig. 3 is a fragmentary sectional plan view illustrating the plunger with its pivoted bracket in position for engaging the beveled operating member on the door latch lever;

Fig. 4 is a fragmentary View illustrating the lower arm of the elevator control lever with the means for locking the same;

Fig. 5 is a view similar to that shown in Fig. 3 but with the plunger thrown forward to operate the door latch;

Fig. 6 is a view similar to that shown in Fig. 4, but with the elevator control lever moved into inoperative position and locked by my improvement;

Fig. 7 is a sectional view similar to the Specification of Letters Patent.

Patented Feb. 12, 1918.

Serial No. 157,705.

views shown in Figs. 3 and 5, but with the bracket moved into locking position by the engagement of the door with the roller mounted on the bracket;

Fig. 8 is a sectional view similar to the views illustrated in Figs. 3, 5 and 7, this view illustrating the function of the flange 011 the end of the door which engages the roller on the bracket to return the bracket to normal position which is shown in Fig. 3 of the drawings;

Fig. 9 is a view illustrating the plunger with the bracket pivoted thereto and the roller rotatably mounted on the bracket;

Fig. 10 is a sectional plan view of Fig. 9, illustrating the spring which serves as an additional means for returning the bracket to normal position after the roller on the bracket has been disengaged by the door; and

Fig. 11 is a fragmentary view showing the beveled operating member on the latch lever, the beveled operating member being enlarged to better illustrate the construction.

By referring to the drawings it will be seen that the elevator car 15 has the usual standard 16, with an elevator control lever 17 pivotally mounted at 18 on the control box 19, which is of the usual construction and i supported on the standard 16. J ournaled in a bearing in the standard 16 there is a shaft 20, to one end of which a lever 21 is secured, this lever 21 being connected with a locking bolt 22 by means of a link 23 which is pivoted at 24; to the locking bolt 22 and at 25 to an arm of the lever 21. The locking bolt 22 is disposed in guideways 26. Secured to the locking bolt 22 there is a collar 27, and a spring 28 is disposed between the upper guideway 26 and the collar 27 to hold the locking bolt 22 yieldingly downwardly. The lower arm of the elevator control lever 17 is provided with guide arms 29 between which there is a recess 30, this construction being provided so that the looking bolt 22 may be moved upwardly into the recess 30 to lock the elevator control lever 17 when the said elevator control lever 17 is in inoperative position, as illustrated in Fig. l of the drawings. However, should the elevator control lever be disposed in operative position when the locking bolt 22 is moved upwardly, it will engage one of the guide arms 29 and will be disposed for movement in the recess 30 as soon as the elevator control lever i again moved to inoperative position. A treadle 31 is pivoted at 32 to a bracket 33 secured to the bottom ofthe elevator car 13, this treadle 31 being connected with the lever 21 by means of a link 34.

An opening 35 is made in the side of the car 15, and at the inner side of this opening there is secured a casing 36, this casing 36 having a guideway 37, and, adjacent the opening 35 in the car, a laterally disposed locking recess 38. A plunger 39 is movably disposed in the guideway 37. An arm 41 is secured to the shaft 20, there be ing a pin and slot connection 40 between the arm 41 and the plunger 39. A bracket 42 is provided with wings 43 which are disposed in re esses 44 in the plunger 39, these wings 43 beii'ig pivoted to the plunger 39 at 45, there being a pin 46 in the plunger 39 which is disposed in curved slots 47 in the wings 43 to limit the movement of the bracket 42 on its pivot 45. The bracket 42 has arms 48 in which a roller 49 is journaledi From the foregoing description, it will be seen that when the elevator operating lever 17 is in inoperative position, as illustrated in Fig. 1 of the drawings, the treadle 31 may be pressed down by the foot of the operator, which will move the locking bolt 22 into the recess 30 to lock the elevator control lever 17, and this movement of the treadle 31 serves by means of the shaft 20 and the arm 41 to move outwardly the plunger 39 with its bracket 42 which carries the roller 49. This outward movement of the bracket 42 and the roller 49 will bring either the bracket 42 or the roller 49 into engagement with a beveled operating member 50 on an arm 51 of a door latch lever 52, provided that the elevator operating lever 17 has been moved into inoperative position with the floor of the car 15 substantially at the bottom of the doorway, which is normally closed by adoor 53 having the door latch lever 52. The said movement of the bracket 42 with its roller 49 against the beveled operating member 50 of the arm 51 of the door latch lever 52, will press the bottom. of the door latch lever 52 against the resiliency of a leaf spring 54 which will move a locking lug 55 out of a recess 56 in the elevator shaft wall. This will unlock the door, inasmuch as the door latch'lever 52 is pivoted to the door 53 at 57. This movement of the plunger 39 with its bracket 42 to bring the bracket 42 with its roller 49 into engagement with the beveled operating member 50 on the arm 5]. of the door latch lever 52, is illustrated in Fig. 5 of the drawings; and, as illustrated in. Fig. 7 of the drawings, when the slide 53 is moved a member 58 on the sliding door 53 will engage the roller 49 to move the bracket 42 on its pivot 45 to the position illustrated in this figure, where the wings 43 of the bracket 42 are disposed in the lateral recess 38 to lock the plunger 39 and prevent it but as soon as the door 53' is closed the v roller 49 is not only freed from the member 58 of the door 53, as illustrated in Fig.3 of the drawings, but a flange 59 at the end of the door 53 engages the roller 49 to move the said roller and the bracket 42 back to i normal position where thewings 43 of the bracket 42 may slide with the plunger 39 rearwardly in the guideway 37. As an additional means of returning the bracket 42 to normal position, I provide a spring 60 which 7 is secured to the plunger 39 and to the bracket 42, which serves to hold the bracket 42 yieldingly in normal position relatively to the plunger 39.

The bracket 42 and the roller 49 are preferably constructed of sufficient height to en gage the beveled operating member 50 on the arm 51 of the door latch lever 52 when the floor of the car is within a few inches of the bottom of the doorway, which is normally closed by the door 53. I

The operating member 50 on the arm 51 of the door latch 52 is beveled so that the arms 48 of the bracket and the roller 49 may readily move into operative position against the outer face of the said member 50, even should the bracket arms 48 and the roller 49 be somewhat extended when they move vertically ith the elevator car into engagement with the said operating mem- It will be understood that when the door 53 has been opened after the elevator oper' ating lever 17 has been moved to inoperative position and the treadle 31 has been pressed downwardly, it is no longer necessary for the operator to keep his foot on the treadle 31, and that the spring 28 will return the elements to normal position immediately on the closing of the door 53.

From the foregoing it will be understood that the means for locking the elevator op erating lever is automatically actuated prior to the opening of the door.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In a safety latch for elevator doors, an elevator control lever, a casing having a guid'eway, a plunger movably disposed in the guideway, a bracket pivoted to. the plunger and having means for engaging a latch for a door, the bracket being disposed to be moved and held by the door in locked position against the casing at the outer side of the guideway as long as the door is open, and means for simultaneously locking the lever and actuating the plunger.

2. In a safety latch for elevator doors, an elevator control lever, a plunger, a bracket movably mounted on the plunger and having means for engaging a latch for a door, a locking member for engagement by the bracket, the bracket being disposed to be moved and held by the door in engagement with the locking member as long as the door is open, and means for simultaneously locking the lever and for actuating the plunger.

3. In combination with a sliding door, a lever having locking means for the door and a beveled operating arm, a locking member, a plunger, a bracket pivoted to the plunger on an axis substantially parallel With the door and at right angles to the path of movement of the door, a roller mounted on the bracket on an axis substantially parallel with the axis of the bracket, the roller being adapted to operatively engage the beveled operating arm on the lever, the roller being disposed for engagement by the door when it is opened to move the bracket into locking engagement with the locking member, and a lange on. the door for moving the bracket free from the locking member When the door is closed.

4. In a safety latch for elevator doors, a locking member, a plunger having means movably mounted for engaging a latch for a door and adapted to be moved and held by the door in engagement with the locking member, and resilient means for holding the said means on the plunger free from the locking member.

5. In a safety latch for elevator doors, a member having a guideway with a recess ex tending laterally from the guideway, a plum ger for moving in the guideway, a bracket pivoted to the plunger and having means for engaging a latch for a door and adapted to 'be moved into the recess and held by the door therein, for locking purposes, and resilient means for holding the bracket out of the recess.

6. In a safety latch for elevator doors, a member having a guideway with a recess extending laterally from the guideway, a plunger for moving in the guideway, a bracket pivoted to the plunger and having means for engaging a latch fora door and adapted to be moved into the recess and held by the door therein for locking purposes, and resilient means for holding the bracket yieldingly on the plunger away from the recess.

7. In a safety latch for elevator doors, a member having a guideway with a recess extending laterally from the guideway, a plunger for moving in the guideway, a bracket pivoted to the plunger, a roller rotatably mounted on the bracket for engaging a latch for a door and adapted to be moved with the bracket into the recess and be held by the door therein as long as the door is open for locking purposes.

8. In combination with a door, a lever having locking means for a door, a locking member, a plunger, a bracket movably mounted on the plunger and having means for operatively engaging the lever, the bracket being disposed for movement by the door into locking relationship with the locking member, and a flange on the door for returning the bracket to normal position.

9. In combination with a door, a lever having locking means for a door, a locking member, a plunger, a bracket movably mounted on the plunger and having means for operatively engaging the lever, the bracket being disposed for movement by the door into locking relationship with the locking member, and means for returning the bracket to normal position.

10. In combination with a sliding door, a lever having locking means for the door and a beveled operating arm, a locking member, a plunger, a bracket pivoted to the plunger on an axis substantially parallel with the door and at right angles to the path of movement of the door, a roller mounted on the bracket on an axis substantially parallel with the axis of the bracket, the roller being adapted to operatively engage the beveled o crating arm of the lever, the roller being disposed for engagement by the door when it is opened to move the bracket into locking engagement with the locking arm, and resilient means for holding the bracket in alinement with the plunger.

11. In a safety latch for elevator doors, an elevator control means, a shaft, a lever secured to the shaft, locking means for the elevator control means operable by the lever, a member having a guidcway With a recess extending laterally from the guideway, a plunger for moving in the guideway, a bracket pivoted to the plunger and having means for engaging a latch for a door and adapted to be moved into the recess and held by the door therein for locking purposes, an arm secured to the shaft and articulated to the plunger, and resilient means for holding yieldingly in predetermined position the locking means for the elevator control means.

THOMAS ACKERSOX MELVILLE.

Copies 01 this patent may be obtained for five cents each. by addressing the Commissioner of Patents,

Washington, D. C. 

